|Figure e-1: Pathological characteristics from brain lesions of patients who developed PML-IRIS.
A: Inflammatory white matter of a PML-IRIS patient. Oligodendrocytes are stained for CAII (red) while astrocytes are stained for GFAP (blue) (bar: 25 µm). Note the absence of overlap of CAII and GFAP showing the specificity of these markers for oligodendrocytes and astrocytes, respectively.
B: Triple staining for CAII (red), SV40 (green) and GFAP (blue) showing a JC-infected oligodendrocyte (arrowhead) and GFAP-positive astrocytes (arrows) (bar: 10 µm).
C: Demyelinating area in a PML-IRIS patient. CAII staining (red) shows the absence of oligodendrocytes while a virus-infected astrocyte is double stained for GFAP (blue) and SV40 (green) (bar: 25 µm).
D: Staining for MAP-2 (green) and SV40 (red) shows the presence of an infected neuron in one of the PML-IRIS cases (bar: 10 µm).
E, F and G show consecutive sections stained by CD3 (E), CD8 (F) and CD4 (G). CD4+ T cells are confined to the perivascular space of a blood vessel while CD8+ T cells infiltrate in the parenchyma (bars: 50 µm).
H: Staining for immunoglobulin shows the presence of multiple plasma cells in the parenchyma (arrowheads) but no deposition of immunoglobulin on parenchymal structures (bar: 25µm).
I: Staining for complement C9neo shows background reactivity in blood vessels (arrowhead) but no deposition in the parenchyma (bar: 25 µm).